int main(int argc, char* argv[])
{
    vector<int> a={2,4,3,6,5};
    sort(a.begin(), a.end(),[](int a,int b){return a>b;});//Lambda表达式,从大到小排序
    for (auto i=a.begin(); i!=a.end(); i++) {  //c++11 auto
        cout<<*i<<" ";
    }
    return 0;
}